Conventionally, to a piping line or arrangement in an aseptic filling system for drink or like, in order to remove dirt or bacteria adhering to an inside of a conduit, a CIP (Cleaning In Place) treatment and SIP (Sterilization In Place) treatment are performed (for example, refer to Patent Document 1, paragraph [0003]).
The CIP treatment is performed, for example, by adding alkaline cleaner such as caustic soda or acidic cleanser to water and circulating such water through a fluid food filling path. According to such treatment, dirt such as remaining material or like adhering to the fluid food filling path can be removed (for example, refer to Patent Documents 1, 2, and 3).
The SIP treatment is performed, for example, by circulating steam or heated water through the fluid food filling path cleaned in the CIP treatment mentioned above. According to such treatment, the interior of the fluid food filling path can be sterilized to thereby provide an aseptic condition (for example, refer to paragraph [0003] of Patent Document 1).
Incidentally, a sterilization treatment line is provided inside a conduit line of an aseptic filling system treating a large amount of product liquid.
Such sterilization treatment line is provided with, though not shown, an upstream side tank for storing a product liquid such as prepared drink and a downstream side tank for storing the sterilized product liquid and supplying the product liquid to a filling machine. The upstream side tank and the downstream side tank are connected through conduit transferring the product liquid, and a high-temperature heating unit for sterilizing the product liquid is provided for an intermediate portion of the conduit. Further, two stages of heating units or sections for heating the product liquid in a stepwise manner are formed to portions of the conduit extending from the upstream side tank toward the high-temperature heating units, and three stages of cooling units or sections for cooling the product liquid in a stepwise manner are formed to portions of the conduit extending from the high-temperature heating unit toward the downstream side tank. By arranging a plurality of stages of the heating units and cooling units, as mentioned above, even a large amount of the product liquid can be properly and smoothly heated to a sterilizing temperature and cooling the product liquid to a normal temperature.
When a container such as PET bottle is filled up with the product liquid by using a filling machine, the product liquid in the upstream side tank is transferred toward the downstream side tank through the conduit under pressure, and in general, during this transferring process, the product liquid is heated in the first stage heating unit from the normal temperature to a temperature of about 65° C., heated in the second stage heating unit from about 65° C. to about 140° C., and maintained in the third stage heating unit at about 140° C. for about 30 to 60 seconds to thereby subjected to the sterilization treatment. Thereafter, the product liquid is cooled in the first stage cooling unit from about 140° C. to about 90° C., cooled in the second stage cooling unit from about 90° C. to about 45° C., and cooled in the third stage cooling unit from about 45° C. to about 30° C. The downstream side tank is filled up with the product liquid of the temperature of about 30° C. from the third stage cooling unit, and the product liquid is then transferred to the filling machine to fill a number of containers such as PET bottles which are conveyed at high speed.
Further, another piping line like the piping line extending from the first stage heating unit to the third stage cooling section is also arranged in parallel therewith. According to such arrangement, even if an accident in which a defective matter such as burning is caused to the product liquid in one of the piping lines by heating, this one piping line is shut off (blocked off), and by using another one piping line, the sterilized product liquid can be transferred to the filling machine. During the operation of such another piping line while sterilizing the product liquid and supplying it to the filling machine, various treatments such as CIP, SIP and positive pressure keeping or maintaining treatments will be performed by suing a CIP-SIP-positive pressure keeping apparatus.